Accelerator physicist for the booster optimization in the FCC-ee collider project H/F

Détail de l'offre

Informations générales

Entité de rattachement

Le Commissariat à l'énergie atomique et aux énergies alternatives (CEA) est un organisme public de recherche.

Acteur majeur de la recherche, du développement et de l'innovation, le CEA intervient dans le cadre de ses quatre missions :
. la défense et la sécurité
. l'énergie nucléaire (fission et fusion)
. la recherche technologique pour l'industrie
. la recherche fondamentale (sciences de la matière et sciences de la vie).

Avec ses 16000 salariés -techniciens, ingénieurs, chercheurs, et personnel en soutien à la recherche- le CEA participe à de nombreux projets de collaboration aux côtés de ses partenaires académiques et industriels.  



Description de la Direction

The IRFU, Institute of research into the fundamental laws of the Universe, is an institute of the Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA Paris Saclay) dedicated to the experimental research in fundamental physics. Near 600 physicists, engineers and technicians work in international projects of research for particle physics, astrophysics and nuclear physics on a large panel of platforms like particle accelerators, scientific satellites or telescopes.

Description de l'unité

The mission of the division of accelerators, cryogenics and magnetism (DACM) is to develop and produce particle accelerators, ion sources, accelerator cavities, cryogenic systems and superconducting magnets for Irfu's scientific programs. Thanks to its advanced skills, the DACM ensures the prime contracting of accelerators or parts of accelerators such as Iphi, the design and prime contracting of accelerator magnets and magnets integrated into detection devices as well as associated cryogenic devices. The DACM has a long experience in conceiving charged particle accelerators. The DACM has for example contributed to the upgrade of the LHC, the HL-LHC project, or to the project of a future proton-proton collider of 100 TeV using the same tunnel as FCC-ee, the FCC-hh project. The DACM also participates to novel accelerating techniques like the laser-plasma acceleration

Description du poste


Physique du noyau, atome, molécule



Intitulé de l'offre

Accelerator physicist for the booster optimization in the FCC-ee collider project H/F

Statut du poste


Durée du contrat (en mois)

24 months

Description de l'offre

The Accelerators, Cryogenics and Magnetism Division of the French Atomic Energy and Alternative Energies Commission (CEA) in Saclay invites applications for a post-doctoral position to optimize the booster of the electron-collider FCC-ee.


One of the provocative questions in particle physics is the understanding of the origin of the particle mass, by exploring the Higgs boson properties, and more particularly its self-interaction. In order to probe the Higgs properties, the electron-positron collider is a powerful tool for precision physics. In this framework, the « Future Circular Collider Innovation Study » (FCCIS) project aims to deliver a detailed conceptual report and to give a sustainable long-term implementation plan of an electron-positron 100-kilometer-long collider with the highest luminosity (value linked to the number of collisions per second) at CERN. The candidate will join an international collaboration grouping top-level laboratories like CERN, DESY, INFN, or KEK. The candidate will focus on the booster, the ring accelerating the electrons and positrons up to the nominal energy before injection into the collider. The DACM leads the efforts on the booster optimisation. The booster has numerous challenges 

One of the challenges is the injection energy. At injection, the magnetic field is so low in the dipoles that the field quality is hardly reproducible from a cycle to another. The candidate will have to fix the minimum affordable energy; this choice will have a great impact on the injection complex.

Another challenge is the ring optics. One of the issues is that the collision energy (and thus the final energy in the booster) depends on the physics case. One optimum optics for a case may be different from another. For the low final energies, the characteristics time to reach the equilibrium emittance (inner value of the beam; the smaller this value is, the better the beam quality is) may be greater than the cycling time. The candidate will have to propose different optics and innovative solutions to get the nominal emittances.

Finally, since the lifetime of the electrons in the collider is low and so that the luminosity stays as constant as possible, the injection into the collider will be “top-up”. This scheme needs a fast increase (in a few seconds) of the magnetic dipole field to go from an energy of about 20 GeV to 180 GeV. The candidate will study how to handle the acceleration in the booster.

The candidate will use MAD-X code [8], a code developed at CERN for optics calculations and will develop its own routines for the tuning procedures and optics correction. 

Profil du candidat

The candidate should have a PhD in accelerator physics and be used to beam optics and accelerator codes like MAD-X. An experience in Python language or in numerical tools is appreciated. The candidate should show some facilities in English communication and teamwork

Localisation du poste



Localisation du poste

France, Ile-de-France, Essonne (91)


Gif sur Yvette

Critères candidat


Anglais (Courant)

Formation recommandée

PhD in accelerator physics


Disponibilité du poste